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<p>[QUOTE=&quot;Conder101, post: 1913626, member: 66&quot;]Camero is right about the extremely low relief making of today making it very difficult if not impossible to have the nice designs of the last century.</p><p><br /></p><p>One reason he didn&#039;t touch on for why the relief is so low today is the coining speeds that are used now to maintain the high coinages.&nbsp; Up through the 1960&#039;s press speeds ranged between 30 and 60 strikes per minute or about one coin per second.&nbsp; Now when the dies come together on the planchet the design isn&#039;t formed instantaneously.&nbsp; It takes some finite amount of time for the metal to cold flow into the recesses of the dies.&nbsp; When they went to clad the harder metal wouldn&#039;t flow as quickly as the silver so the relief was reduced in the dies so the metal wouldn&#039;t have to flow as far.</p><p><br /></p><p>As press speeds increased to around 100 strikes per minute, relief had to be reduced even more (spaghetti hair).&nbsp; Today presses run at 750 strikes per minute.&nbsp; The cold flow which used to have 1/4 to 1/2 second to fill the dies now has to do so in less than 1/20 of a second.&nbsp; So if the die relief isn&#039;t very low the metal just can&#039;t move far enough to fill the die before they open up again.[/QUOTE]</p><p><br /></p>

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